New isolation methods for new microorganisms from soil samples and their phylogenetic analysis and long-term preservation
| Project/Area Number |
17510198
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Resource conservation science
|
|---|
| Research Institution | Kitasato University |
|---|
Principal Investigator |
TAKAHASHI Yoko Kitasato University, Kitasato Institute for Life Sciences, Professor, 北里生命科学研究所, 教授 (80197186)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SHIOMI Kazuro Kitasato University, Kitasato Institute for Life Sciences, Professor, 北里生命科学研究所, 教授 (40235502)
MATSUMOTO Atsuko Kitasato University, The Kitasato Institute, Researcher, 基礎研究所, 研究員 (20300759)
|
|---|
| Project Period (FY) |
2005 – 2006
|
| Project Status |
Completed (Fiscal Year 2006)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2006: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 2005: ¥2,100,000 (Direct Cost: ¥2,100,000)
|
|---|
| Keywords | Soil microorganisms / Unknown microorganisms / Soil aggregates / Superoxide / SOD and catalase / Low-molecule radical scavengers / New genus and species / Long-term preservation |
|---|
| Research Abstract |
The number of microorganisms that have been successfully identical and cultured in vitro represents only a small portion of the total existing in nature. It has been estimated that the number of known bacteria is less than 10% of the total number of bacterial species in the world. We are interested in unknown microorganisms as novel resources for the screening of new bioactive compounds.
To isolate new microorganisms, we took notice of the environmental differences between the outside and inside of soil aggregates, which are clumps of soil particles. As aggregates are not fractured in soil suspensions by mixing, microorganisms living inside of the aggregates are not isolated by conventional methods. Therefore, we attempted to selectively isolate bacterial strains from inside soil aggregates after fracturing them by sonication. The strains isolated from inside and outside the aggregates were compared with each other in the same soil sample for colony appearance on two types of agar medium. Unique strains in inside or outside were 40% and 55%, respectively, and common isolates were 5%. These data were also confirmed by taxonomical position of each strain on the basis of 16S rDNA partial sequence analysis.
In the course of searching for factors which promote bacterial colony growth, we found that using an isolation agar medium supplemented with superoxide dismutase and catalase increased the number of colonies isolated from a soil sample. In this project, effect of low-molecule radical scavengers, vitamin C, catechin and rutin, were investigated for the bacterial growth. The number of colony and taxonomical diversity of these isolates were enhanced by addition of catechin and rutin Three new genera, Patulibacter, Oryzihumus and Humihabitans, and 9 new species were proposed from strains isolated by this method.
Lyophilization method showed high viability for long-term preservation.
|
Report
(3 results)
Research Products
(27 results)
